Mining machine having digging arms with impact means



May 4, 1954 Y MINING MACHINE HAVING DIGGING ARMS WITH IMPACT MEANS Filed June l, 1950 F. CARTLIDGE 2,677,537

9 Sheets-Sheet l vvv A I N VEN TOR.

Mil/CMS* rroRNEy F. CARTLIDGE May 4, ,1 954 MINING MACHINE HAVING DIGGING ARMS WITH IMPACT MEANS 9 Sheets-Sheet 2 Filed June l, 1950 NN NNN Y Nm mll @IIL v m w IN1/ENT?.

tlzdge 7 ym TTQRNEV May 4, 1954 F. CARTLIDGE 2,677,537

MINING MACHINE HAVING DIGGING ARMs WITH IMPACT MEANS @Si f 3N, L NN IN V EN TOR.

i; Yank Jartldge r B Trae/Vey F. CARTLIDGE May 4, 1954 MINING MACHINE HAVING DIGGING ARMS WITH IMPACT MEANS 9 Sheets-Sheet 4 Filed June l, 1950 NVENToR.

rt/idge ,4 T rok NEy F. CARTLIDGE May 4 1954 MINING MACHINE HAVING DIGGING ARMS WITH IMPACT MEANS Filed June l, 1950 9 Sheets-Sheet 5 dye mr WR Nd May 4, 1954 F. CARTLIDGE 2,577,537

MINING MACHINE yHAVING DIGGING ARMS WITH IMPACT MEANS Filed June l, 1950 9 Sheets-Sheet 6 INVENTOR.

TTQQNEV May 4, 1954 F. CARTLIDGE 2,677,537

MINING MACHINE HAVING DIGGING ARMs WITH IMPACT MEANS Filed June l, 1950 9 Sheets-Sheet 7 IN V EN TOR.

BY artlia'ge @M5/.m

F. CARTLIDGE May 4, 1954 MINING MACHINE HAVING DIGGING ARMS WITH IMPACT MEANS Filed June l, 1950 9 Sheets-Shea?I 8 77/sy PEA/57:64

/A/E F3465 NCEE45/A/6 INVENTQR. da lge 7. fipa@ ATTORNEy Mink Patented May 4, 1954 Frank Cartlidge, Chieago, lill., assigner te Goodman Manufacturing Company, Chicago, lill., a

cerporation oi illinois l Claire-ls.

ing of coal, salt, ore and the lille directly ein a soild mine face without the usual nnderenttlng, shooting and loading operations.

A principal ohjeot oi this intention is to prem vide a new improved eornhined rein" ing and leading machine capable of produc more lump material and utilizing less power i the amount of material mined than with i mining and loading machines. En coi tion the improved machine comprises f cooperating digging elements which ar mounted on a for sii`L ..rneons swinging movement toward the mine tace to remove material in a manner which in nt i compared with the operation oi a pair ci' to gs or pineers driven into the mine face, therey euttiafT and dislodging material in large ln i; sizes and with a minimum of lines or dust.

Previous attempts to carry out direct r operations by tongor pineer-lilre arrangenie have met with failure when applied to mining or" hard. materials such as coal, ore and salt hecanse of failure to appreeiate the proper method oi applying power to the digging elements.

In the present invention, as graphically portrayed in Figure 3, power is utilized rnost effe@- tively by application through eccentric such as a crank or cani. shaft which applies an increasing ferce to the digging elements they are driven into the mine aee. An ancillary eatnre includes the provision of impact mechanism which into operation automatically to apply a of hammer blows to the digging elements whenever they are stalled, or about to be stalled, py resistance in the mine face.

A speeinc object is the provision oi batter clutch means in the drive for the digging ele ments which is normally inoperative but goes into automatically to a termined abnormal reaction between mfaee and the digging elements to store driving energy and release it in a series of sharp impacts to overcome the abnormal resistance niet in the face.

Another object, broadly, is the provision of driving means for the digging element or eiements which will apply a series of hammer blows to the digging element s whenever resistance to digging exceeds a predetermined value.

Another object is the provision of driving means so arranged that tlie hammer blows will be applied to the digging elements in sirnni" taneous timed sequence to facilitate straightline advance of the digging elements into the 2 Without this arrangement, ii the f s permitted to he struck lirst i i; element and then on the other, power would he Wasted in slewing the head oi the Inaeliine inelectively in one direction or the other.

A further object is the provision of driving means for the digging elements in which a single driving member, herein speci .really disclosed as a crank shaft or earn, is utilised to actua-te both digging elements so they will swing forward and 'lic'iward in positively simultaneous, timed sequence whereby the machine will dig straight anead and not slew ofi toward one side or the other.

A still further oiijeet is the provision oi a minoi 'the char aeter described in which e tongd ae digging elements are mounted on auxiliary frame which itself is mounted for l i e retraetinle mover" ent with respeot to the main iraine so the digging elements mayfed into the mine iaee while the main frame is stationary-tins being distinetly advantageous that it provides a fixed platform, stalle irrespective oi roughness in the door sin-fase, for driving the digging elements i to tne race.

[ino-ther object the provision oi a combined mining and leading machine having concurrently swingahle digging arms mounted on a portatile main frame for universal movement, including forward and backward movement, and down movement, and side to side movement, whereby an entire mine iaoe may be mined out wither-.t tramrning the machine forward or sidewise.

invention will appear in the following descri tion taken in eonnection with drawings in wlcli:

Figure 'l is a plan view oi a continnons Cutting and loading machine employing one embodiment ei the present invention;

Fig. 2 is a side view oi inaeliine shown in Fig. l;

Fig. 3 is a fragmentary enlarged view of 'i showing more particularly the p oi the machine Constructed in aeeordanee wirJLA tire present invention;

Fig. 3a is a cross-sectional view oi taken (Fig.

Fig. 6a is a cross-sectional view of Fig. 6, taken along line 6a-6a;

Fig. 7 is an enlarged fragmentary plan view of the arrangement for driving the digging arms and shows the details of the battering clutch means employed to overcome abnormal resistance met by the digging arms;

Fig. 8 is a graphical representation of the increasing force applied by the digging arms as they penetrate the mine face; and

Fig. 9 is a diagrammatic view of another driving arrangement wherein auxiliary motor means is employed for applying a series of hammer blows to the digging elements responsive to a predetermined abnormal reaction between the mining face and one or both of the digging elements; this embodiment differs from that covered by the previous figures in that separate motor means is employed to apply the hammer blows.

General arrangement Referring now more particularly to the drawings, the general arrangement illustrating the present invention is best shown in Figs. 3, 4, 5 and 6, the remainder of the machine, particularly the rear end, being similar to that disclosed in applicants prior application, Serial No. 116,- 684, filed September 20, i949, which is herein included merely for the sake of disclosing a complete machine serving as an environment for the present invention.

A portable or mobile main frame I3 (Figs. 3 and 4) is suitably mounted on and propelled about the mine by a pair of laterally spaced, continuous tread devices II. A horizontally swingable intermediate frame I2 is mounted on the forward end of the main frame for pivotal movement about a vertical axis I2a-I2a of sleeve 24 The intermediate frame i2 has an extensible frame I4 supported and guided thereon for forward and backward movement relative thereto and has the cutting and dislodging arrangement of the present invention, generally designated I5, projecting forwardly therefrom. The arrangement I5 will be described in detail subsequently.

The lower reach of an endless, center-strand chain conveyor I9 is mounted on the machine and runs forwardly in a forwardly and downwardly disposed section 2li (Fig. 5) of the extensible frame I4 and the upper reach runs upwardly and rearwardly from the forward end of that section, then runs backward beyond the main frame Il) over a horizontally and vertically swingable rear discharge end 2i for discharging the mined material into a suitable receptacle, such as a mine car, a rubber-tire-mounted shuttle car or any of the well known forms of conveyors of the type used underground in mines. A gathering mechanism, generally designated 23, is provided at the forward end of the frame section 2i] to pick up: the mine material from the ground and discharge it onto the receiving end of the conveyor.

For horizontally swinging the front end of the machine, the intermediate frame i2, which carries the extensible frame I4, is pivotally mounted on the upright sleeve 24 which depends from and is herein shown as being formed integrally with an upper plate 26 of the main frame I0, and is recessed within the lower plate of the main frame, all as shown in Fig. 5. The intermediate frame I2 extends forwardly beyond the sleeve 24 along the top of the main frame Ii! and is slideably supported for horizontal swinging movement on an arcuate segmental bearing 29 which is carried at the front of the main frame. An arcuate shouldered-under forward end portion 30 of the main frame I0 is slideably engaged by a segmental retaining guide 3| secured to the bottom of an arcuate flange 32, which latter depends from the forward end of the intermediate frame I2 and functions to hold the intermediate frame against vertical displacement during operation of the machine.

The intermediate frame I2 is swingable about the axis I2a-I2a of sleeve 24 and fixed in any desired position by means of a double-acting cylinder 33, the latter being suitably pivoted at its head end to a bracket 34 extending laterally from a side frame member 35 of the main frame I0. A piston rod 36, extensible from cylinder 33, is pivotally connected at its forward end to an arm 31 extending laterally from and herein shown as being formed integrally with the intermediate frame I2.

The intermediate frame I2 acts as a slideable support for the extensible frame I4. As shown in Fig. 3a, the intermediate frame I2 has two longitudinally extending upstanding wall portions 38 defining a central channel through which the conveyor I9 passes. Upper and lower supporting arms 39 and 4U, respectively, extend outward from the wall portions 38 and have longitudinally extending vertical support and guide plates 44 at the outer ends thereof. The plates 44 extend beyond the forward and rear of the arms 39 and 4B. The upper and lower edge portions of the plates 44 function as slideable supports for the extensible frame I4 which has, at the rear and on each side thereof, a motor 45. The motors 45 are herein shown as being well known forms of electric motors and serve to drive the cutting and dislodging arrangement I5 and the gathering mechanism 23 in a manner to be described in detail. As shown in Fig. 3a, the motor housings 46 have shouldered guides 4l extending inwardly from and along the upper and lower edges thereof and opening toward each other for slideably engaging the upper and lower edges of the guide plates 44.

As shown in Fig. 1, double-acting cylinders 52, having piston rods 5I extensible therefrom, are provided on each side to extend or retract the extensible frame I4 relative to the intermediate frame I2 along the support and guide plates 44 for moving the cutting and dislodging arrangement I5 toward and away from the mine face while the main frame I0 is stationary on the treads II. The cylinders 5B are clamped to the inside of the guide plates 44 by longitudinally spaced clamps 53 and they extend beyond the forn ward ends of plates 44. As shown in Fig. 3a, the piston rods 5I extend through and are secured, as by nuts 5l, to ears r54 which extend inwardly from the housing structures 46 of the extensible frame.

Gathering mechanism the axis of the crank and maintain it at any particular pivotal position when desired.

Impact-generating means Attention will now be directed to the novel means for rotatably driving the crank shaft 2 and for applying a series of hammer blows to it when necessary to overcome an abnormal resistance encountered by the digging arms in the mine face.

In Fig. 6 the driving arrangement between the two motors 45 and the crank shaft and gathering means is shown. For simplication, to expose the parts of the gathering means, the motor on the far side of that figure is shown shifted beyond its normal position which is indicated in broken lines. To further clarify the figure, only the connections for driving the crank shaft are shown on the near motor and only those for driving the gathering mechanism are shown on the far motor. It will be understood, however, that each motor is connected to drive its corresponding end of the crank shaft and one of the gathering mechanism driving sprockets 1|.

Referring now, rst, to the driving arrangement whereby each motor drives one end of the crank shaft, each rotor shaft 22S operates through a hammer blow mechanism 221 (to be described in detail) to turn a bevel gear 228. The latter meshes with and drives a bevel gear 24S which, in turn, rotates shaft 25| and turns pinion 252. The latter is connected, through speed reducing gears 253 and 252, to drive the main gear 256 on one end of the crank shaft. This arrangement is duplicated on both sides of the machine.

Referring now to the arrangement for driving the gathering mechanism, reference is made to the far motor in Fig. 6 where the rotor pinion 251 is shown driving gear 253 through a reach gear 259. Gear 25S is connected to rotatably drive worm 28| through universal joints 252 and and intersplined shafts 2654-356. The worm 26| meshes with worm gear 261 and drives shaft 258 supporting the driving sprocket 1|. This arrangement, as pointed out abcve, is also duplicated on each side of the gathering apron 63. The intersplined connection between members 252 and 2% compensates for the variation in distance between each motor 45 and its corresponding worm 26| as the gathering mechanism is tilted up and down about the axis of its trunnions 59.

The hammer blow means, generally designated 221, comprises in this instance a battering clutch, best shown in Fig. 7. The battering clutch has .a housing 269 and a bore 21| lined with a bearing or bushing 222. Journaled within said bushing, for rotatable and reciprocable movement, is a battering member 223, threaded internally at a steep angle as shown at 214. Reciprocablc movement in one direction is limited by an inturned stop shoulder 21:` and in the opposite direction by an annular retainer 211 held in place by bolts 21S. One end portion of the internally threaded member 213 is provided with a slot 219 which engages a similarly formed flat-sided projection or extension 23| provided on the end of the rotor shaft 246. In the present instance, the opposite sides or edges of the projection 23| comprise spaced parallel surfaces 282, and the mating surfaces 233 in the member 213 are of like configuration. The projection 28|, however, is considerably narrower than the slot 219 in order to provide sufcient clearance for the battering member 213 to move into and out of engagement with the projection when hammer blow action is required, as will be described.

The bevel pinion 248 is keyed to a shaft 284 by a feather 286, the shaft being rotatably supported in a bearing 281 mounted in one end of the gear housing 288. The opposite end of shaft 284 is formed with steep, external threads 289 which are engaged with the internal threads 214 in the battering member 213. The latter is normally urged to the left (Fig. 7) against stop plate 211 by a coil spring 29| which is footed against an inturned shoulder 292 formed within the housing 28S. Under the condition shown in Fig. 7, which may be considered normal, the battering member 273 will engage the projection 28| within slot 21S for transmitting rotational force steadily from the motors t5 to their corresponding gears 25 through the respective gear trains. An annular spacer flange 293, interposed between the housing 259 and 288, carries a grease retainerl 224. Between the reciprocable member 213 and the spring 29| is interposed a ball bearing mem ber 29S to provide for rotation of the member 213 with respect to the spring.

In operation each of the impact generating arrangements, generaliy designated 241, functions, independently of the other, as follows:

Normally, torque will be transmitted from rotor shaft 225 to the battering member 213 through interengagement of the projection 28| and the slot 13. The driving torque between member 223 and the shaft 224 will tend to cause the member Z'ES to rotate relative to the shaft and climb, to the right, up the threads 289. Under normal load conditions, however, this tendency will be completely or-set by the spring 22| which will maintain the member 213 at its left-hand limit, as shown in Fig. '1. Under abnormal load conditions, as where the digging arms 2|1 are stalled in the mining ace, or about to be stalled, the battering member 213 will climb to the right (Fig. 7) upon the shaft 284 to disengage the slot 219 from the projection 28|. The rotor 246 will then race for approximately one-half a revolution and re-engage the battering member with a hammer blow as the slot of the latter is pressed back onto the extension 28|. Thus, kinetic energy will be permitted to build up in the rotor for approximately half a turn and applied suddently to the digging arm drive to permit the arms to overcome the abnormal resistance met in the face. These hammer blows will be repeated until the digging arms are again moving smoothly into the face. The torque between the shaft 28d and the rotor 246 will be proportional to the resistance met by the arms in the mine face and the torque at which hammer blow action begins to occur will be predetermined by the strength of spring 25|.

The hammer blow means may be incorporated at any desired position between the motors and the digging arms. In the present instance it is considered advantageous to drive the two hammer blow units directly from the two motors, so as to be on the high speed side of the crank 2| i and, therefore, impart hammer blows to the digging arms at a high frequency. With this arrangement it is recognized that, under some conditions, the eifectiveness of the hammer blows may be somewhat reduced by energy absorption in the gears and other parts of the drive; hence, in certain service conditions, it may be preferable to place the hammer blow generating means closer to the digging arms.

With the present arrangement, it will be noted that the two hammer blow units lill provide for advantageous, independent and ilegible operation. lf one should fail for any reason, the other would still operate so as to avoid a possible shutdown which might result if both Went out of use. Furthermore, while both units operate independently, nevertheless they do cooperate in applying the above-mentioned battering action to the two opposite ends of the crank shaft.

The motors will not necessarily be synchronized so that, in operation, they need not run at identical, synchronous speeds. On the contrary, there are certain practical advantages of perniitting motors to run independently over a range of conditions whereby, at times, the battering clutches Elli will be in phase to support one another as to magnitude, at other times coinpletely out of phase so as to double the ireduenoy of impacts applied and, at still other times, at intermediate phase conditions, thereby providinvf an automatically variable battering arrange-- ment to apply hammer blows to the mine face over a wide range oi variations both as to magni-I tude and frequency, so as to automatically seekl out the conditions under which the coal, salt or ore 'oreals down most easily. Under some conditions of mining, it may be found advantageous to deliberately run the two motors @lil at different speeds, or to run one at a hired speed and the other at a varying speed, so as to introduce a iixeol or variable beat in the action of the immeans on the digging arins.

While one speciiic hammer blow means Zfll has been described, any other arrangement capable oi generating blows responsive to a predeter- 'ned torque or resistance in the mine face may be employed.

Referring now to Fig. 7, the housing and bearing arrangement for certain of the driving gears, not previously mentioned, will be described. The shaft Edi is held at its ends by bearings Ztl, maintained in place by retainer caps itil. |llhe shaft Edil, carrying gears 252i and itil, is similarly mounted in bearings Sti, maintained in place by retainer caps itil.

.as pointed out above, previous, arrangements for driving swingable digging arms have been rnsatisfactory in that the load applied to the digig arins decreased they penetrated the mine ce. In contrast to this idea, attention is dito 3 which is a graphical representation showing that, in the present miner, the digging force actually increases as the arins penetrate the mine face. Fig. 8 is to oe considered in connection Fig. B, where, at the front end of the machine, a line is drawn indicating the proximate location oi the mine iace as, in

pactice, it would be, a few inches ahead of the hoorn before digging begins. Starting at the mine .tace a number or" positions indicated 1, 2, 3, etc., these positions being the location of the tips of the digging arins throughout their range oi penetration within the mine face. These positions comprise the abscissa oi the curve in Fig. il. A representative range oi iorces, exertable the end oi each digging arm by use of a practical sise inotor, comprises he ordinate ci the curve. For example, from 8, if the toreo applied by each arm at position "1 is 1800 pounds, then, at position 5, it will be in the saine order oi magnitude, about lill@ pounds, and from 'then on it will rise to e606 pounds position 9 and something higher at position (K10-) l@ Operation In operation, the miner will be advanced into a room Sti) (Fig. l) and centrally located with its endless treads il parallel to the sides of the room. liter completing a out to denne a spherioally shaped iace Elli, the extensiole traine will be retracted to the limit of its travel by applying pressure through suitable hydraulic means (not shown) to cylinders The machine will then be tramrned forward on the treads il by suitable driving and control means (not specifically shown) until the tips il@ or" digging arms Ell' are within a few inches of the iace, it being understood the digging arms will have previously been moved to their extreme retracted position, as shown in Fig. 6. rEhe rear end section oi the conveyor i9 will be swung to discharge onto a suitable receptacle such as a shuttle oar (not shown). Then, by application of hydraulic pressure to cylinder 533, the intermediate frame i2 will be swung to align the digging elements with one side oi the mine face. The boom 2GB? will be lowered by application of pressure to, or release from, cylinder 2li to lower the digging elements to the floor. The motors Will then be energiaed by suitable means (not shown) to swing the digging arms ill' into the mine face, the battering clutches going into operation automatically when needed to overcome abnormal resistance in the face. After advancing through positions l-lO (as shown in Fig. 3) with increasing force (as shown in Fig. 8) the arms will be swung baci; to 'their retracted position for a new bite at a higher level as the boom is swung upwardly by pressure admitted to cylinder 25.2 to traverse the face from floor to roof. As the material is dislodged, it will be transferred by the gathering mechanism to the conveyor lil, which then moves it to the baci; of the machine for discharge onto a suitable receptacle.

In one construction oi the miner, provision is made for extending the extensible frame Id about 24 inches. In mining very hard materials, the extensible iran/1e may be set to dig, say, 6 inches into the iace. Then, alter the head has traversed all the way irorn the floor Jo ceiling, the extensible frame it will be advanced another 6 inches or so, with respect to the main frame, for the return pass to the iloor level. By making repeated up and down passes, following extensions ci the frame lli, the face may be mined in to the 'lull extent allowed by the extensibility of frame without changing the position of the main traine.

Following mining out one side of the face, for the full depth permitted Toy the extensibility of frame l il, the latter will be retracted and swung about axis lEc--la until the digging arms are aligned with the adjacent uncut portion of the face. rIhis portion will then be mined out to the extent permitted by the extensibility oi frame Eli and these operations will be repeated until the entire face is mined from top to bottoni, and from side to side to the maximum depth permitted by the machine. lThis entire series of operations will have been performed without changing the position of the trarne. When it is completed the frame lll and the arras Ell will once more be retracted to their limits and the machine tra-mmol forward to repeat the series of operations in the new iace.

By tieing the movement oi the two digging elements 2li together with the cominon inember 2l l, the hammer blows must necessarily be applied to the digging elements, through the member 22|, in simultaneous timed sequence. This facilitates straight-line advance of the pair of digging elements into the mine face. If the hammer blows were permitted to be applied first to one element and then to the other, much of the effectiveness of the impacts would be dissipated by uselessly slewing the head one way and then the other. By applying the hammer blows to the two digging elements in simultaneous timed sequence, the pair will advance straight into the face.

It will thus be seen that the present invention provides a mining and loading machine which drives the digging elements 2|i into the mine face, with forces which increase with the amount of penetration, to rapidly dislodge material, directly from a solid mine face in relatively large pieces and with a minimum of power consumption.

Modification employing separate power source for impact-generating means `Eig. 9 shows a modied form of drive for one end of the crank shaft 2H. It will be understood that the same arrangement might be duplicated for the opposite end of the crank shaft. In this arrangement, the battery elements 241 (Fig. 6) will be operably connected through the crank shaft to one of the main driving motors 45 and an auxiliary motor 260. Control means 24e is connected in the drive between the main motor and the digging elements. Impact generating means, in this case including a battering clutch already described under the designation of numeral 241, is connected in the drive between the auxiliary motor and the digging elements. The impact generating means is controlled by the control means 24!) for superimposing a battering or vibratory load on the relatively continuous load applied by the main driving motor 45 whenever the resistance encountered by the digging elements in the mine face rises above a predetermined point, as will novv be described in detail.

As shown in Fig, 9, the main drive gearing between the motor 45 and the crank shaft 2|| is identical to that described for the previous embodiment except that a straight shaft 235 replaces the battering clutch 241, the latter now being connected to drive the gear 256 directly through pinion 255; and the control means 24E! takes the place of gear 253 and shaft 299.

The control means 24!) is mounted on a shaft 299e. On the right end portion of shaft 2891i is keyed the pinion 254, the latter being held :against longitudinal movement a C-ring 35|. Held on the opposite end portion by a C-ring 352 is a relatively wide gear 253cv. Adjacent the C-ring 352 the shaft is formed with steep threads 353 engaged with mating internal threads 354 in gear 253a. At the end of the threaded section is a collar 356. Between the gear 253a and pinion 254 is a compression spring 351, seated at its right end on an annular bearing member 358 which is mounted for limited rotatable movement with respect to the pinion 254. While the particular torque-responsive control means described may be utilized, it will be apparent that any other means capable of responding to the reaction between the digging arms and the mine face may be utilized to control the application of the battering clutch 241 to the crankshaft.

A normally open limit switch 359, mounted adjacent the gear 2530i, has a roller-carrying extension 36| engageable with the end face of the gear. When the gear moves to the right, the element 36| follows, permitting switch 359 to close.

Referring now to the auxiliary motor portion of the circuit arrangement shown in Fig. 9, the battering clutch 241 is driven by the motor 2E@ through a chain 265. An electrically actuatable connecting clutch 250, being shown only diagrammatically, is actuatable to connect the battering clutch to a pinion 255. With this rangement the auxiliary motor 280 and the battering clutch may, if desired, be run continuously while the mining machine is operating, so to be up to speed when needed, and the connecting clutch 250 will operate instantaneously to trans'- mit impact loads to the crankshaft through pinion 255 whenever the limit switch 359 is closed.

In operation, the main driving motor '45 and the auxiliary motor 260 will normally both be running. However, unless the resistance met in the mine face rises above an abnormal amount as predetermined by the strength of spring 35i, only the main driving motor 45 will actually carry any load. This load will be transmitted through pinion 252a and gear 253a, and, because the spring 351 resists climbing movement of the gear 2.53ct up the threads 353, the pinion 254 will be driven as a unit with the gear 2530l to transmit power to the crank shaft. During this time, the auxiliary motor 260 is rotating freely by reason of the face that clutch 250 remains energized.

Whenever the digging elements encounter an abnormal resistance in the face, the reaction will be transmitted backward through the gearing to cause control gear 253a to be shifted to its right hand limit, against collar 356, where it will be held so long as the abnormal resistance in the face prevails. This will energize clutch 253 through switch 359 causing the battering clutch 241 to go into effect instantaneously to superimpose a battering load upon that applied by the main motor 45 to the crank shaft,

Under some conditions of operation it may be preferable to run the auxiliary motor 259 only when vibratory load is called for. The arrangement in Fig. 9 may be revised for such operation merely by eliminating the clutch 25|! and connecting the switch 259 to energize the auxiliary motor directly.

While a preferred embodiment of the present invention has been illustrated and desori ed in detail, it should be understood that the invention is not limited to the specific apparatus or arrangement of parts disclosed.

I claim:

1. In a combined mining and loading machine for dislodging material directly from a mine face, mobile frame means; a pair of cooperating digging elements pivotally mounted on said frame means for simultaneous swinging movement toward and away from the mine face; drive means for said digging elements including crank means, linkage means connecting said crank means with said digging elements for swinging the latter toward and away from the mine face upon rotation of the crank means, motor means for rotatably driving said crank means, and battering clutch means between the motor means and the crank means effective to impart a series of hammer blows through the crank means to the digging elements responsive to a predetermined torque exerted on said clutch means by said motor means.

2. In a combined mining and loading machine .fOl' dslodging material directly from a mine face,

10. In a combined mining and loading machine for dislodging material directly from a mine face,

pair of pointed cooperating pincer-like digging elements pivotally mounted on mobile frame means for simultaneous swinging movement thereof to move their points in an arcuate path toward and away from one another and the mine face; drive means for swinging said elements simultaneously toward one another while entering said face including means for applying, in simultaneous timed sequence, a series of hammer-blows to said digging elements to facilitate straight-line advance oi the mobile frame means into the mine face.

11. In a combined mining and loading machine for dislodging material directly from a mine face, a pair of pointed cooperating pincer-like digging elements pivotally mounted on mobile frame means for simultaneous swinging movement thereof to move their points in an arcuate path toward and away from one another and the mine face; drive means for swinging said elements simultaneously toward one another while entering said face including means automatically operable responsive to a predetermined reaction between said elements and said face to apply a series of hammer blows to said elements for overcoming abnormal resistance to digging.

12. In a combined mining and loading machine for dislodging material directly from a mine face, a pair of pointed pincer-like digging elements pivotally mounted for simultaneous swinging movement to move their pointed portions in co-planar arcuate paths toward and away from one another and the mine face, main and auxiliary motor means connected to drive said elements simultaneously toward one another and into said face, impact generating means associated with said auxiliary motor means effective at times to apply the power from said auxiliary motor means to said digging elements in a series of hammer blows, control means between said main motor means and said elements actuatable to one condition responsive to increase of reaction between said elements and said face above a predetermined abnormal value, said control means being operably associated with said impact generating means to actuate the latter responsive to change of said control means to its said one condition, whereby said digging elements are normally driven by said main motor means and whereby further, upon rise of said reaction to its said predetermined value, said auxiliary motor means will be operable through said impact generating means to superimpose a vibratory load on both of said digging elements to overcome said abnormal reaction.

13. In a combined mining and loading machine for dislodging material directly from a mine face, a pair of pointed pincer-like digging elements pivotally mounted for simultaneous swinging movement to move their pointed portions in coplanar arcuate paths toward and away from one another and the mine face, a first power means operably connected to said digging elements to concurrently drive the latter toward one another and into the face under conditions of normal reaction between the elements and the face, a second power means including impact generating means associated with both of said digging elements for driving the latter into the face under conditions of abnormal reaction between the elements and the face, and control means associated with said digging elements and said second power means and being effective to actuate said impact generating means responsive to an abnormally high reaction between the elements and face for driving the digging elements in a vibratory manner to overcome said abnormal reaction.

14. In a combined mining and loading machine for dislodging material directly from a mine face, a pair of pointed pincer-like digging elements pivotally mounted for simultaneous swinging movement to move their pointed portions in co-planar arcuate paths toward and away from one another and the mine face, power means operably associated with said digging elements for driving the latter toward one another and into the face, control means operably associated with said digging elements and operable to an abnormal condition responsive to rise of reaction between said face and said elements above a predetermined value, and means for modifying the operation of said driving means, responsive to change of said control means to its said abnormal condition, to apply a series of hammer blows to said face through said digging elements.

15. In a combined mining and loading machine for dislodging material directly from a mine face, digging means including a pair oi pointed pincer-like digging elements pivotally mounted for simultaneous swinging movement to move their pointed portions in co-planar arcuate paths toward and away from one another` and the mine face, drive means effective to exert digging pressure against both of said elements, and control means for said drive means operable responsive to a predetermined reaction between said elements and said face to modify the operation of said drive means to cause the latter to apply a series of hammer blows to said elements for overcoming abnormal resistance to digging.

16. In a combined mining and loading machine for dislodging material directly from a mine face, mobile frame means; a pair of cooperating digging elements pivotally mounted on said frame means for simultaneous swinging movement toward and away from the mine face; drive means for said digging elements including eccentric means, linkage means connecting said eccentric means with said digging elements for swinging the latter toward and away from the mine face upon rotation of the eccentric means, motor means for rotatably driving said eccentric means, and battering clutch means between the motor means and the eccentric means effective to impart a series of hammer blows through the eccentric means to the digging elements responsive to a predetermined torque exerted on said clutch means by said motor means.

17. In a combined mining and loading machine for dislodging material directly from a mine face, a pair of pointed cooperating pincer-like digging elements pivotally mounted on mobile frame means for swinging movement toward and away from one another and the mine face; and drive means for swinging said elements toward one another while entering said face including means for applying a pulsating force to each of said elements in a direction to press it into the face.

18. In a combined mining and loading machine for dislodging material directly from a mine face, a pair of pointed cooperating pincer-lilre digging' elements pivotally mounted on mobile frame means for swinging movement toward and away from one another and the mine face; means interconnecting said arms for simultaneous forward and backward movement relative to the face; and

the face. 5

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date l 0 1,234,912 Kuhn et al July 31, 1917 1,389,421 Corrigan Aug. 30, 1921 1,508,634 Wilson Sept. 16, 1924 1,563,153 Brackett et a1 Nov. 24, 1925 Number Number:

Name Date Jameson Mar. 23, 1926 Morgan Mar. 26, 1929 Hughes Sept. 27, 1932 Prebensen Jan. 111, 1941 Cartlidge Sept. 21. 1943 Tibbals June 10, 1347 Levin Aug. 22, 1950 FOREIGN PATENTS Country Date Austria Jan. 10, 1923 

